Monoclonal antibodies to human fibronectin will be used in the genetic analysis of this important cell surface molecule. Genes controlling the structure and function of fibronectin will be mapped to human chromosomes. Immunochemical selection procedures will be developed to select for hybrid cells expressing human fibronectin. A two dimensional gel spectrophotometer has been developed which can visualize isozymes on gels with methods analogous to those used in conjunction with the spectrophotometer fluorimeter. We will use this device to map new human genes.